1. Field of the Invention
This invention is related to a viscous material dispenser, and particularly to a multiple use dental syringe adapted to lock in place a viscous material capule.
2. Description of the Related Art
Various dispensing devices for dispensing viscous dental compositions and the like are known in the art, such as, for example, disclosed in U.S. Pat. Nos. 6,422,866; 6,379,152; 6,135,771; 6,116,414; 6,099,307; 6,059,570; 5,871,355; 5,707,234; 5,489,207; 5,336,088; 5,306,147; 5,267,859; 5,172,807; 5,165,890; 5,125,836; 5,061,179; 4,813,871; 4,619,613; 4,492,576; 4,472,141; 4,384,853; 4,330,280; 4,315,743; 4,295,828; 4,198,756; 4,084,320; 3,828,434; 3,760,503; 3,618,216; 3,581,399; 3,436,828; 3,346,147; 2,903,794; 2,837,824; 2,648,906; 683,075; Des. 461,247; Des. 460,822; Des. 435,292; Des. 359,560; Des. 357,141; Des. 359,119; Des. 357,536; Des. 353,673; Des. 334,803; and Des. 315,956; the subject matter of all of which are incorporated herein by reference in their entireties.
FIG. 1 is a view of a conventional syringe 30xe2x80x2 for dispensing viscous dental compositions, in conjunction with a capule 40 or the like, taken from U.S. Des. 359,560 to Mitchell, the subject matter of which is incorporated herein by reference in its entirety.
The front end portion of the syringe 30xe2x80x2 extends only partially around the circumference of the barrel. An opening for inserting a capule or the like is thus formed where the front end circumferential portion of the barrel is absent. A slot for supporting a capule or the like is also formed by the partial inside circumference of the front end portion of the syringe.
The capule 40 can be inserted into the syringe 30xe2x80x2 through the opening and mounted in the slot thus formed. The capule 40 can similarly be removed from the syringe 30xe2x80x2 out of the slot and through the opening.
When positioned in the slot, the capule 40 is supported by the front end portion that extends partially around the circumference of the barrel. The capule is not supported where the opening is formed where the front end circumferential portion of the barrel is absent.
In U.S. Pat. No. 4,384,853 to Welsh, a dental syringe having a snap-fit front end barrel construction is disclosed. In the snap-fit type construction, a lower portion of the front end of the barrel is open and a viscous material containing cartridge or the like can be snap-fit in position where the front end is open. With such a construction, it is possible for a snap-fitted cartridge to accidentally and undesirably be ejected from the barrel through the open lower portion of the barrel.
U.S. Pat. No. 5,125,836 to Dragan et al. discloses a viscous material extruder with a slot located a full circumference front end for receiving a nozzle of a cartridge. A shoulder extending substantially the full circumference of the front end holds the cartridge. However, the slot remains open and it is possible that a cartridge or the like could accidentally and undesirably become dislodged and/or ejected through the slot.
A number of devices have been contemplated to encircle a cartridge mounted in a syringe type dispenser. For example, U.S. Pat. No. 4.295,828 to Rudler discloses a viscous material extruder with a front end of the barrel provided with a hinging section for loading and locking a cartridge in place at the front end of the barrel. However, the Rudler device requires a number of relatively complex parts that can increase the cost of manufacturing the syringe type dispenser.
It is an object of this invention to overcome deficiencies and limitations of the known viscous material syringe dispensers.
It is a further object of this invention to provide a viscous material syringe dispenser having a simple and economical mechanism in which a capule can be inserted into the viscous material syringe dispenser and then locked into place where the capule is supported about the entire circumference thereof.
The above and other objects of this invention are achieved by a viscous material dispenser that is adapted to lock into place a capule or the like for containing the viscous material. The capule and the viscous material contained therein can be inserted into a syringe type dispenser for the controlled application of the viscous material. The dispenser includes a locking mechanism mounted on the syringe type dispenser to securely retain the capule within the syringe type dispenser while the viscous material is being applied from the syringe type dispenser. The locking mechanism can be positioned so that it rotates around and over the outer circumference of the barrel of the syringe type dispenser. The locking mechanism can be rotated to an open position from which a capule can be inserted or removed from the syringe type dispenser and a closed position from which a capule is locked into position for dispensing.